Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

chrome/browser/prerender/prerender_link_manager.cc

Index: chrome/browser/prerender/prerender_link_manager.cc
diff --git a/chrome/browser/prerender/prerender_link_manager.cc b/chrome/browser/prerender/prerender_link_manager.cc
index e54068de7cf91f6c489d271c538c0dcac6c5815c..1044220b7da8c0f16d819878a6bdeba7d49748e9 100644
--- a/chrome/browser/prerender/prerender_link_manager.cc
+++ b/chrome/browser/prerender/prerender_link_manager.cc
@@ -74,13 +74,15 @@ enum RelTypeHistogramEnum {
 };
 
 void RecordLinkManagerAdded(const uint32_t rel_types) {
-  const uint32_t enum_value = rel_types & (RelTypeHistogramEnumMax - 1);
+  const RelTypeHistogramEnum enum_value = static_cast<RelTypeHistogramEnum>(
+      rel_types & (RelTypeHistogramEnumMax - 1));
   UMA_HISTOGRAM_ENUMERATION("Prerender.RelTypesLinkAdded", enum_value,
                             RelTypeHistogramEnumMax);
 }
 
 void RecordLinkManagerStarting(const uint32_t rel_types) {
-  const uint32_t enum_value = rel_types & (RelTypeHistogramEnumMax - 1);
+  const RelTypeHistogramEnum enum_value = static_cast<RelTypeHistogramEnum>(
+      rel_types & (RelTypeHistogramEnumMax - 1));
   UMA_HISTOGRAM_ENUMERATION("Prerender.RelTypesLinkStarted", enum_value,
                             RelTypeHistogramEnumMax);
 }